We can write the equation in point-form in this case. The equation should be:
y-y1 = m(x-x1)
y and x can be any point in the line, so we leave them just like that in the equation, we don’t have to add any numbers to them. m is the slope of the line, and (x1, y1) is the given point in the line, which is (-1, 1) in this case.
Now, just substitute the number in,
y - 1 = -2 [x - (-1)]
y - 1 = -2 (x+1)
y - 1 = -2x - 2
2x + y + 1 = 0
So, 2x + y + 1 = 0 is your answer.